Hydrocarbyl butanediol disulfate phosphate-free detergent compositions

ABSTRACT

NOVEL PHOSPHATE-FREE DETERGENT COMPOSITIONS COMPRISE A MIXTURE OF 2-ALKYL OR ALKENYL-1,4-BUTANEDIOL DISULFATES AND NON-PHOSPHATE BUILDERS AND ADDITVES.

United States Patent O 3,634,269 HYDROCARBYL BUTANEDIOL DISULFATE PHOSPHATE-FREE DETERGENT COMPO- SITIONS Robert G. Anderson, San Rafael, Califi, assignor to Chevron Research Company, San Francisco, Calif. No Drawing. Filed Jan. 10, 1969, Ser. No. 790,483 Int. Cl. Clld 3/06'6 U.S. Cl. 252-531 6 Claims ABSTRACT OF THE DISCLOSURE Novel phosphate-free detergent compositions comprise a mixture of 2-alkyl or alkenyl-1,4-butanediol disulfates and non-phosphate builders and additives.

BACKGROUND OF THE INVENTION The present invention is concerned with the field of synthetic detergents and more particularly with novel 2- hydrocarbyl butanediol disulfates suitable as biodegradable and phosphate-free detergent compositions.

Increased concern over water pollution has produced significant changes in household detergents. Initially, major emphasis has been placed on producing biodegradable surface-active components for detergents. The shift to linear surface-active materials, including linear alkyl benzene sulfonates (LAS) and alpha-olefin sulfonates, etc., has reduced pollution attributed to nonbiodegradability.

However, the above-mentioned surface-active materials are inadequate in terms of soil removal in the absence of phosphate builders. Increasing evidence appears to indicate that phosphates contribute to the growth of algae in the Nations streams and lakes. This algae growth poses a serious pollution threat to the maintenance of clear, good domestic Water supplies.

In contrast to the problems encountered with the above-described commercial detergent compositions, the present invention provides novel, biodegradable detergent compositions which exhibit high detergency and soil removal ability in the absence of phosphate builders.

SUMMARY OF THE INVENTION Novel phosphate-free detergent compositions comprise a mixture of Z-hydrocarbyl-1,4-butanediol disulfa-tes of the formula wherein X is hydrogen or a water-soluble, salt-forming cation and R is a hydrocarbyl radical containing from 14 to 36 carbon atoms; and non-phosphate builders and additives.

R above may be represented by the formula wherein R and R are hydrogen or saturated or unsaturated, straight-chain or branched-chain hydrocarbyl radicals containing from to 35 carbon atoms. In a preferred embodiment, the hydrocarbyl radical R is a saturated or unsaturated straight-chain group containing from 14 to 24 carbon atoms. More preferably, R is saturated and contains at least 18 carbon atoms.

The hydrocarbyl butanediol disulfates as described within the scope of the present invention may be prepared by the reduction of alkenyl succinic anhydrides to produce either alkenyl or alkyl diols and subsequent sulfation of the diols. The alkenyl succinic anhydrides may be produced by the familiar condensation of maleic anhydride with an olefin.

By an alternative method the alkenyl succinic anhydride may be reacted with an alcohol to produce the diester and then reduced to the alkyl butanediol. By controlled reduction, unsaturated portions in the alkenyl chain may be preserved.

The novel 2-hydrocarbyl-1,4-butanediol disulfates of the present invention may be prepared by sulfating 2- hydrocarbyl-l,4-butanediols where the hydrocarbyl radical may be alkyl or alkenyl selected from, but not limited to the following: tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosy], docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, hentriacontyl, dotriacontyl, tritriacontyl, tetratriacontyl, pentatriacontyl, hexatriacontyl, tridecenyl, tetradecenyl, pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, nonadecenyl, eicosenyl, heneicosenyl, docosenyl, tricosenyl, tetracosenyl, pentacosenyl, hexacosenyl, heptacosenyl, octacosenyl, nonacosenyl, tricontenyl, hentriacontenyl, dotriacontenyl, tritriacontenyl, tetratriacontenyl, pentatriacontenyl and hexatriacontenyl.

The diols may be converted to disulfates by sulfation with chlorosulfonic acid, S0 oleum and other known sulfating agents. The sulfated product may be neutralized with aqueous basic solutions containing compounds such as hydroxides, carbonates, and oxides of the alkali metals, alkaline earth metals, ammonium and other water-soluble salt-forming cationic agents.

The following examples describe the preparation of the Z-hydrocarbyl-1,4-butanediol disulfates and their evaluation as detergent compounds.

EXAMPLE 1 Preparation of alkenyl succinic anhydride A mixture of 405 g. (1.5 moles) of internal olefins having from 18 to 20 carbon atoms and an average molecular weight of 270 was stirred slowly with 49 g. (0.5 mole) of maleic anhydride in a 1-liter, 3-necked, round bottom flask equipped with an explosion-proof stirrer, a drying tube condenser, and dropping funnel and continuously flushed with nitrogen. The reaction was continued for about 7 hours at a gradually increasing temperature starting at C. and stopping at 212 C. At the end of this time, infrared analysis showed less than 1.0% of maleic anhydride remaining. The mixture was transferred to a distillation flask. Excess olefins were removed by distillation at approximately 1 mm. pressure until about 5% olefin remained, as shown by a vapor phase chromatographic analysis. The stripped bottoms product from this distillation was then heated and filtered through Celite to give 101 g. of crude alkenyl succinic anhydride.

EXAMPLE 2 Preparation of 2-n-eicosenyl-1,4-butanediol A flask similar to that used in Example 1 was flushed with nitrogen and charged with 30 g. (0.8 moles) of lithium aluminum hydride. One pint (473 cc.) of tetrahydrofuran was carefully added with stirring. A solution of 189 g. (0.5 moles) of n-eicosenyl succinic anhydride in 1 pint of tetrahydrofuran was added at such a rate as to maintain reflux. Reflux was continued for three hours after addition of the anhydride. 3 g. of lithium aluminum hydride was added and heating continued for 2 hours. After standing overnight, 1 g. of lithium aluminum hydride was added and the mixture was heated at reflux for 2 additional hours. A small sample was worked up and infrared analysis showed the absence of the carbonyl band.

The reaction mixture was cooled in ice and 500 ml. of 10% hydrochloric acid carefully added. The mixture was transferred to a separatory funnel containing 2500 ml. of water and 500 ml. of diethyl ether. After shaking and separation of layers, the aqueous phase was extracted with 500 ml. of ether. The combined ether extracts were washed with 500 ml. portions of water, saturated sodium bicarbonate solution, and water. The solution was dried over anhydrous sodium sulfate and the solvent removed. The residue (110 g., 60% yield) was recrystallized from hexane to give 2-eicosenyl-1,4-butanediol, melting point 54.555.5 C. The infrared spectrum showed adsorbance at 965 cm.- indicating the presence of a double bond.

EXAMPLE 3 Reduction of 2-alkenyl-1,4-butanediol In a 500 ml. Fisher-Porter bottle, 40.0 g. of 2-n-eicosenyl-1,4-butanediol was dissolved in 250 ml. of absolute ethanol. To this was added 4.0 g. of palladium on carbon catalyst. Hydrogen was added to the bottle to give 60 p.s.i.g. of pressure. The contents were heated to 50 C. and agitated with incremental addition of hydrogen until a total of 200 p.s.i. of hydrogen was taken up. The solution was filtered while warm to remove the catalyst, and then the alcohol was removed by evaporation at 50 C. to give 37 g. of a 2-n-eicosyl-1,4-butanediol having a melting point of 65.5 C. An infrared spectrum showed the complete absence of double bonds.

EXAMPLE 4 Preparation of 2-hexadecyl-1,4-butanediol The procedure of Example 2 was followed, except that 27 g. (0.7 moles) of lithium aluminum hydride and a solution of 162 g. (0.5 mole) of a commercially available Z-n-hexadecyl succinic anhydride were substituted as reactants. The final residue (144 g., 91.5% yield) was recrystallized from hexane to give 2-n-hexadecyl-l,4- butanediol.

Other alkyl succinic anhydrides are available commercially or may be obtained by the mild, controlled catalytic hydrogen of the corersponding alkenyl succinic anhydride with hydrogen in the presence of a catalyst such as platinum or nickel.

EXAMPLE 5 Sulfation of 2-n-hexadecyl-1,4-butanediol A 500 ml., 3-necked, round bottom flask fitted with a stirrer, dropping funnel, and thermometer was flushed with nitrogen and charged with 18.2 g. (0.06 mole) of Z-n-heXadecyI-butane-1,4-diol and 50 ml. of dry methylene chloride. After cooling to C. and using vigorous stirring, a solution of 11.5 ml. (0.17 mole) of chlorosulfonic acid in 10 ml. methylene chloride was added at a rate which maintained the 10 C. temperature. Stirring was continued for minutes after addition. The whole reaction mixture was then transferred to a dropping funnel. The flask was charged with 6.4 g. of sodium hydroxide dissolved in a mixture of ml. of Water and 75 ml. of ethanol and cooled to 510C. The acid solution was then added dropwise, keeping the temperature below 10 C. After minutes additional stirring, pH was adjusted to 89 with dilute sodium hydroxide. Sodium bicarbonate (0.2 g.) and ethanol (100 ml.) were added, and the mixture was heated to remove methylene chloride. Temperature was maintained at C. for 0.75 hour. Precipitated salt was removed by hot suction filtration. The filtrate was cooled and 100 ml. of water added. De-oiling was accomplished by extraction with four 75 ml. portions of n-pentane (total oil=0.2 g. or 0.5%). Solvent was evaporated from the aqueous phase, and there was obtained 31 g. (99%) of 2-n-hexadecylbutane-1,4-diol disulfate, disodium salt. The product was recrystallized twice from ethanol and dried in a vacuum oven.

4 EXAMPLE 6 Sulfation of 2-n-eicosenyl-1,4-butanediol Substantially the same procedure of Example 5 was followed, except that 22.1 g. (0.06 mole) of 2-n-eicosenyl- 1,4-butanediol and 9 ml. (0.14) mole of chlorosulfonic acid were used. 21.8 g. of Z-n-eicosenyl-1,4-butanediol disulfate, disodium salt was obtained.

Detergency of the compounds of the present invention has been measured by their ability to remove natural soil from cotton cloth. By this method small swatches of cloth, soiled by rubbing over face and neck, are washed with test solutions of detergents in a mini-washer, and the refiectances of the various cloths measured and compared. The results obtained are expressed as a detergent index value.

The detergent index value is obtained by comparing and correlating the reflectance value results from the test solution with the results from two defined standard solutions.

The two standard solutions are selected to represent a detergent formulation exhibiting relatively high detersive characteristics and a formulation exhibiting relatively low detersive characteristics.

By testing each soiled cotton cloth against the standardized solutions as well as the test solutions, the results can be accurately correlated. The two standard solutions were prepared from the following detergent formulation:

Ingredient: Weight percent (LAS) linear alkylbenzene sulfonates 25 Sodium triphosphate 40 Sodium silicate 7 Carboxymethylcellulose 1 Sodium sulfate 19 Water 8 The standard exhibiting high-detersive characteristics was prepared by dissolving 1.5 g. of the above formulation in 1 liter of 50 p.p.m. hard water (calculated as calcium carbonate and /3 magnesium carbonate). The low detersive standard contained 1.0 g. of the formulation dissolved in 1 liter of 180 p.p.m. water (same basis).

The test solutions consisted of the 2-hydrocarbyl-1,4- butanediol disulfates prepared as in Example 5 and formulated with other ingredients to give the following phosphate-free formulation:

Ingredient: Weight percent 2-hydrocarbyl-1,4-butanediol disulfate 25 Sodium sulfate 59 Carboxymethylcellulose 1 Sodium silicate 7 Water 8 Two test solutions were prepared from each formulation. The first consisted of 1 g. of formulation dissolved in 1 liter of 50 p.p.m. hard water. The second consisted of 1.5 g. of the formulation dissolved in 1 liter of 180 p.p.m. hard Water.

In the test procedure one side of small white cotton swatches was uniformly soiled with natural human face and neck soil, and then cut into four 12 mm. squares. These squares were each sewn onto the center of a separate clean white cotton disc, 3.5 cm. in diameter with the soiled side out. Each cotton disc was placed in a separate glass vessel, 4.0 cm. in diameter and 8.0 cm. tall. Then 7 ml. of a detergent solution was added, along with ten inch in diameter stainless steel balls.

One of the four glass vessels was charged with the 50 p.p.m. water test solution, another with the 180 p.p.m. water test solution, another with the high standard, and the last one with the low standard.

The glass vessels were stoppered, placed in a constant temperature bath at F., and agitated at 900 cycles/ minute for 10 minutes. At the end of this time, the swatches were removed from the glass vessels and were hand-squeezed dry. They were rinsed three times for one minute each time in Water of the same hardness as was used in the wash cycle. The excess water was squeezed out, and then the swatches were placed on a paper towel to dry. I

When dry, the soiled portions were measured for whiteness by standard photoelectric reflectance procedure. The detergency index of each test sample was then calculated, using the following formula:

Detergency Index-0.60

+ 57 (Refiec. Test Samp.Reflec. Low Stand. Refiec. High Stand.-Reflec. Low Stand.

For comparison, a commercially available LAS detergent formulation was measured by the detergency index rating. The formulation was as follows:

Ingredient: Weight percent LAS 25 Sodium sulfate 59 Sodium silicate 7 Carboxymethylcellulose 1 Water 8 In general, the compatible ingredients other than water may be employed in amounts ranging from 60 to 900 parts and, preferably, from 70 to 250 parts by weight per 100 parts of hydrocarbyl butanediol disulfate utilized.

In addition, the detergent compositions may comprise from 0 to 700 parts by weight of water per 100 parts of butanediol disulfate employed. The lower range of water concentration is used for compounding particulate formulations which may contain 15 parts of water per .100 parts of the butanediol disulfate. The upper range of water concentrations are used to prepare liquid formulations. For this use, 100 to 400 parts of water per 100 parts of butanediol disulfate are preferred.

As will be evident to those skilled in the art, various modifications of the present invention can be made or followed in light of the foregoing disclosure and discussion, without departing from the spirit or scope of the following claims.

I claim:

1. A phosphate-free detergent composition consisting essentially of a mixture of (1) as an active ingredient, a compound of the formula:

wherein X is hydrogen or a water-soluble, alkali metal, alkaline earth metal and ammonium cation and R is an alkyl or alkenyl radical containing from 14 to 36 carbon atoms and represented by the formula:

R2(])H s wherein R and R are hydrogen or an alkyl or alkenyl TABLE L-ANALYSIS AND DETERGENCY PERFORMANCE OF DISODIUM 2-HYDROCAR- B YL-1,4-B UTANEDIOL DISULFATES Detergency index Disodium disulfate sulfur analysis p.p.m. 180 p.p.m.

Example Hydrocarbyl group Calculated Found wt. cone. wt. cone.

7 Decyl 0.44 0.36 8 Dodecyl 13. 8 13. 6 0. 36 0. 42 9 Tetradecyl 0.68 10-- O. 64 0.66 11 0. 92 0. 89 12 0. 80 0.88 13-- 0. 93 0. 95 14.- 11.2 0. 0.63 0.75 15 10. 7 9. 0.88 0.82 16 Mixed I1-C1QC 2 alkenyl 11. 4 11. 0. 76 0.80 17 Mixed sec-(h -C alkenyl 0. 90 0.92

EXAMPLE 18 A 2-alkyl-1,4-butanediol disulfate was prepared by previously described procedures from a mixture of C and C l-olefins obtained by the ethylene growth reaction. A detergency evaluation in 50 p.p.m. hard water showed this material to be about equivalent to the docosyl derivative in removing natural soil from cloth in the absence of phosphate builders.

Additional compatible ingredients may be incorporated into the detergent compositions prepared in accordance with the present invention to enhance their detergent properties. Such ingredients may include, but are not limited to, anti-corrosion, anti-redeposition, bleaching and sequestering agents, optical whiteners and certain organic and inorganic alkali and alkaline earth salts other than phosphate, such as inorganic sulfates, carbonates or borates and the organic salts of the amino polycarboxylic acids; e.g., trisodium salt of nitrilo acetic acid, tetrasodium salt of ethylenediaminetetracetic acid, etc. The preferred compatible ingredient is sodium sulfate.

radicals containing from 0 to 35 carbon atoms; and (2) in an amount of from 60 to 900 parts by weight per parts of active ingredient, at least one additional compatible ingredient selected from the group consisting of alkali metal and alkaline earth sulfates, carbonates and borates.

2. A detergent composition as in claim 1, wherein X is selected from the group consisting of sodium, potassium, ammonium, calcium and magnesium.

3. A detergent composition as in claim 2, wherein R is selected from the group consisting of n-octadecyl, n-nonadecyl, n-eicosyl and docosyl hydrocarbyl radicals.

4. A detergent composition as in claim 2, wherein R and R are independently selected from the group consisting of saturated straight-chain or branched-chain alkyl radicals, unsaturated straight-chain or branched chain alkenyl radicals.

5. A detergent composition as in claim 4, wherein water is present in an amount of from 100 to 400 parts by weight per 100 parts of active ingredient.

6. A detergent composition as in claim 5, wherein a non-phosphate builder selected from the group consisting of sodium and potassium sulfate is present in an amount of from 60 to 900 parts per 100 parts of active ingredient.

References Cited UNITED STATES PATENTS 2,802,789 8/1957 Stayner 252l38 3,158,639 11/1964 Klass et al. 260-456 8 OTHER REFERENCES 6709714 l/l968 Netherland.

LEON D. ROSDOL, Primary Examiner P. E. WILLIS, Assistant Examiner US. Cl. X.R. 252-550 

